Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C15/00—Tyre beads, e.g. ply turn-up or overlap
  • B60C15/02—Seating or securing beads on rims
  • B60C15/024—Bead contour, e.g. lips, grooves, or ribs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C15/00—Tyre beads, e.g. ply turn-up or overlap
  • B60C15/02—Seating or securing beads on rims
  • B60C15/024—Bead contour, e.g. lips, grooves, or ribs
  • B60C15/0247—Bead contour, e.g. lips, grooves, or ribs with reverse bead seat inclination, i.e. the axially inner diameter of the bead seat is bigger than the axially outer diameter thereof
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T152/00—Resilient tires and wheels
  • Y10T152/10—Tires, resilient
  • Y10T152/10495—Pneumatic tire or inner tube
  • Y10T152/10819—Characterized by the structure of the bead portion of the tire

Definitions

• the present invention relates to a tire with a radial carcass reinforcement, in particular, with a low aspect ratio H / S, H being the height of the tire on the rim and S its maximum axial width, intended to be mounted on a rim of which at least one seat is tilted outwards and extended axially outwards by a low projection. It relates more particularly to the beads of such a tire.
• the solution described above is not entirely satisfactory from the point of view of gum tearing, with the consequence of the possibility of injury from the overturning of the carcass reinforcement, which is not very compatible with aesthetics on the one hand and share with the need for security, naturally required by users.
• the object of the invention is to propose a different solution to remedy the drawbacks described above and consists in replacing the protuberance of the bead intended to be radially in contact with the projecting protrusion by a protective rib or protuberance of appropriate and localized shape. also adequately.
• the tire with a radial carcass reinforcement and intended to be mounted on a rim J of which at least one seat is inclined towards the outside and extended axially outside by a projection of low height, said projection comprising an axially outer wall, comprises at least one bead having a heel axially inside and a bead point axially outside, said bead being provided with a protective rib or protrusion extending in the circumferential direction, this protective rib having at least one point axially further from the equatorial plane than the axially outer wall of the projection of the rim in order to protect said rim.
• This tire is characterized in that, mounted on its mounting rim and seen in meridian section (that is to say in a cutting plane containing the axis of rotation): said circumferential protective rib is delimited axially to the externally by an axially external face connected to the external flank and bead walls by radially respectively upper and lower faces, the point or points of the axially external face of the axially outermost protective rib is / are at a distance e at least equal to 0.5 mm from the axially outer wall of the rim protrusion, - the radial distance from between the radially innermost point of the axially outer face of the rib and the radially outermost point of the projecting projection is greater than 4 mm, the angle of the segment joining the end points of the axially outer face of the protective rib with a say ction perpendicular to the axis of rotation is at most equal to ⁇ 10 °, the profile of the lower connection face between the axially outer face of the protective
• the tire according to the invention once mounted on its rim offers very good protection against external attacks from said rim. Furthermore, the remoteness of the rib according to the same characteristics makes it possible to avoid tearing of rubber from the bead, which ensures the durability of the protection.
• the distance e is between 1 and 1.5 mm.
• the length of the segment joining the end points of the axially outer face of the protective rib is between 5 and 10 mm so as to obtain good protection of the rim without excessively increasing the weight of the tire.
• the angle made by the segment joining the end points of the axially outer face of the protective rib, with a direction perpendicular to the axis of rotation, is preferably at most equal to ⁇ 5 ° in order to avoid overpressures localized when in contact with an external object and also in order to avoid excessively localized wear by friction.
• connection face can be cylindrical, frustoconical or curved, said face being joined to the wall of the bead and to the axially outer face by slight rounded in order to, as known per se, avoid stress concentrations.
• the upper connection face extends substantially between the radially outermost point of the face axially outside the protective rib and a point on the outer wall of the sidewall of the tire defined as being at a radial distance at least equal to twice the length of the segment joining the end points of the axially outer face of the protective rib.
• This upper connection face is preferably located entirely radially outside a straight line passing through the radially outermost point of the face axially outside the protective rib and tangent at this point to said profile. , this straight line making an angle at most equal to 55 ° with the equatorial plane, which makes it possible to offer a minimum of grip to obstacles and thus limit their indentation by allowing a possibility of sliding between the obstacle and the rib of protection.
• This upper connection face seen in meridian section, may in particular have the shape of an arc of a circle.
• the external walls of the protective rib with at least one reinforcement comprising a textile reinforcement (for example Nylon®) embedded in a rubber mixture of an appropriate nature (and in particular resistant to abrasion).
• a textile reinforcement for example Nylon®
• FIG. 1 shows a first variant of tire according to the invention
• FIG. 2 shows a second variant of tire according to the invention having at least on one side a particular bead profile.
• FIG. 1 shows a partial and schematic cross-section of a tire P according to the invention mounted on a mounting rim J.
• the sidewall 8 and the bead 5 of a tire P for a passenger vehicle of size 205-650 R 440A, shown in FIG. 1, include a carcass reinforcement 1, anchored in the bead 5 by winding around a bead wire anchoring 2 by going axially from the inside of the tire to the outside to form a reversal 10.
• Said reversal 10 completely surrounds a profile 3 disposed axially outside the anchoring rod 2 of the carcass reinforcement 1, said profile 3 being, in section, in the form of an angular sector of substantially triangular shape having a vertex located approximately radially under the rod 2 (that is to say between the axis of rotation and said rod ), two sides starting from said vertex and a third side opposite said vertex.
• Profile 3 is formed of a rubbery mixture, having in the vulcanized state a Shore A hardness equal in the example described at 95.
• the rod 2 is surmounted radially on the outside of a profile 6 of rubbery mixture of hardness Shore A, less than 40. Radially outside of the profile 3 and axially outside of said profile 6 is arranged another profile 7 of rubber mixture with low hardness compared to the hardness of the mixture of profile 3.
• the rim J on which the bead 5 described above is mounted, comprises a frustoconical seat 42 extended axially on either side by two frustoconical faces: axially outside by the face 410 of a projection 41 of low height and axially inside by the face 43 connecting said seat 42 to a bearing support bearing surface 44, said supporting support acting to support the tire in the event of pressure loss.
• the face 410 is extended by the face 412 in the form of an arc of a circle on the plane of the figure, the latter face 412 extending by an axially external face 411.
• the bead 5 of the tire P In its part radially inside with respect to the bead wire 2, the bead 5 of the tire P, shown inflated, is in contact by its seat 90 with the seat 42 of the rim J and axially on the outside by a wall 91 against the face 410 of the projection 41. In the extension of the wall 91 of the bead, a wall 92 partially envelops the surface 412 of the projecting projection 41.
• the axially outer wall of the bead 5 is provided with a protective rib T, delimited on the outside by three faces which, seen in meridian section in FIG. 1, have generators AB, CB, AD, the generator AB connecting the two other generators CB and
• the faces bear the name of their generator, for example, the face having for line the line AB is called, in the present documenta face AB.
• the generator AB of the axially outermost side AB of the rib T is in the case presented a straight line making an angle ⁇ with a perpendicular to the axis of rotation of the tire at most equal to 10 ° (in in the case presented, this angle is equal to 5 °); the distance D AB between the end points A and B is preferably between 5 and 10 mm.
• the point A radially furthest from the axis of rotation is here the point of the rib T axially furthest from the equatorial plane.
• This generator AB is joined, radially inside, to the wall of the bead by the generator BC which is, in the example described, a line segment, the latter extending by another line segment CC making an angle ⁇ substantially equal, in the case presented, to the angle ⁇ .
• This last segment CC is connected with the part 92 of the bead in contact with the part 412 radially outside the projecting projection 41.
• the point C corresponds to the last point of the part 92 of the bead 5 which can come into contact with the upper part 412 of the projection 41 when the tire is inflated.
• the point of intersection B of the generator AB with the generator BC is located at a distance from a straight line ⁇ parallel to the axis of rotation and passing through the radially outermost point of the upper part 412 projection 41, equal to the distance e increased by 6 mm.
• the distance e is worth in the example described 1.5 mm and corresponds to the distance separating axially, in the plane of the figure, a straight line perpendicular to the axis of rotation and passing through the point of the rib T axially furthest away from the equatorial plane, from the straight line Tl perpendicular to the axis of rotation and tangent axially outside to the projection 41.
• the point C limiting the generatrix BC of the rib T is obtained as being the point of intersection between the external profile of the bead and a straight line, denoted Tl, perpendicular to the axis of rotation and tangent to the face 411 axially to the outside of the projection 41.
• this point C must be located radially outwards with respect to a virtual straight line passing through the last point C 'of the bead in contact with the projection 41 and the point B so as to generate flexibility in bending the appropriate bead to avoid any jamming of the rib between an external obstacle and said projection.
• the radial distance d separating the points C and C is noted d; preferentially, this distance d is greater than the distance separating the point B from the line ⁇ minus the axial distance e.
• the generatrix AD of the radially upper face AD of the rib T is in the form of a circular arc whose center of curvature is located axially outside the tire and whose tangent Ta at point A d intersection between the faces AB and AD makes with the equatorial plane an angle ⁇ equal to 45 °.
• the face AB of the protective rib is rectilinear; of course, this face AB could be of any shape and in particular curved.
• the protective rib which is continuous in the circumferential direction with the variant presented with FIG. 1, could also be discontinuous.
• This same face AB can be provided with a plurality of reliefs extending in a direction making an angle other than zero with the circumferential direction in the manner of what is described in the international application PCT 99/64258 already cited.
• FIG. 2 shows a bead of a tire according to another variant of the invention.
• the references given in this FIG. 2 as soon as they are identical to those used in FIG. 1, refer to the same structural elements as those described with the support of FIG. 1.
• the bead 5 of the tire P comprises a carcass reinforcement 1 anchored around a bead wire 2 going from the inside of the tire outwards to form a loop around a rubber profile 3 and form a turning 10 axially between the carcass reinforcement 1 and the bead linkage 2.
• the bead 5 shown corresponds to the bead located on the vehicle exterior side of the tire mounted on its rim.
• This rim J comprises rim seats 42 inclined towards the outside and terminated axially on the outside by protrusions 41 against which the bead tips 5 come into contact.
• the projection 41 of the rim comprises, in the extension of the rim seat 42, a first inclined portion 410 which is substantially rectilinear, itself extending radially outwards by a portion 412 in the form of an arc of a circle; this latter part 412 is connected axially to the outside to an external face 411 which is substantially rectilinear and perpendicular to the axis of rotation.
• the bead 5 is provided with a protective rib T whose points axially furthest from the face 411 are at a distance e equal to 1.5 mm.
• the profile of the protective rib T comprises a face AB in the form of an arc of a circle extended radially outwards by an arc of a circle between the point A and a point D located at a distance D AD equal to twice the distance D AB measured in the radial direction between points A and B.
• the tangent Ta at point A to said profile in an arc forms an angle ⁇ with the radial direction (perpendicular direction to the axis of rotation) which in this case is equal to 45 °.
• the profile AB of the protective rib T is extended radially inwards by a substantially linear profile BC (the point C being obtained as the intersection between the profile of the bead radially below the rib T and a straight line Tl perpendicular to the axis of rotation and tangent to the external face 411 of the projection 41).
• the point C is located at a radial distance d from the radially furthest points from the projection 41 which in the present case is equal to 3 mm.
• Point B is located at a radial distance equal to 4 mm from the edge 412 of the projection 41.
• the profile of the face BC is radially outside a straight line ⁇ passing through point B and through the last point C of the bead in contact with the projection (inflated tire).
• the profile of the bead 5 between point C and the point C of connection between said bead 5 and the protective rib T is formed so as to extend the profile of the bead in contact with the inclined part 410 of the projection 41 without there being any contact on the part radially outside 412 of the projection.
• the profile between C and C is an extension of the profile of the inclined part 410.
• the profile of the bead between C and B is located radially outside and axially inside a virtual straight line ⁇ passing through said points B and C.
• This latter feature profile of the bead not bearing on the radially part external of the projection
• this arrangement does not require the use of a rim protection rib, however, it is clear that a tire capable of being mounted on a rim as described will preferably be provided with such a rib protection at least on the side most sensitive to external aggressions.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Tires In General (AREA)

Applications Claiming Priority (3)

Publications (2)

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• 2002
  • 2002-07-25 AT AT02751161T patent/ATE317772T1/de not_active IP Right Cessation
  • 2002-07-25 EP EP02751161A patent/EP1414656B1/de not_active Expired - Lifetime
  • 2002-07-25 CN CNB028151135A patent/CN1277701C/zh not_active Expired - Fee Related
  • 2002-07-25 KR KR10-2004-7001279A patent/KR20040023696A/ko not_active Withdrawn
  • 2002-07-25 DE DE60209231T patent/DE60209231T2/de not_active Expired - Lifetime
  • 2002-07-25 JP JP2003516824A patent/JP2004535976A/ja not_active Ceased
  • 2002-07-25 WO PCT/EP2002/008279 patent/WO2003011616A1/fr not_active Ceased
• 2004
  • 2004-01-21 US US10/762,620 patent/US6886617B2/en not_active Expired - Fee Related

Non-Patent Citations (1)

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